modernize bigmod()

1 files changed, 19 insertions, 11 deletions

diff --git a/big.c b/big.c
index d5341ac..fc9a452 100644
--- a/big.c
+++ b/big.c
@@ -398,25 +398,33 @@ word bigdiv(word x, word y)
   return q;
 }
 
-word bigmod(x, y)		/* may assume y~=0 */
-word x, y;
+/* may assume y~=0 */
+word bigmod(word x, word y)
 {
-  word s1, s2;
+  word s1 = big_is_negative(y);
+  word s2 = s1;
+
   /* make x,y positive and remember signs */
-  if (s1 = big_is_negative(y))
+  if (s1) {
     y = make(INT, digit0(y), rest(y));
-  if (big_is_negative(x))
-    x = make(INT, digit0(x), rest(x)), s2 = !s1;
-  else
-    s2 = s1;
+  }
+
+  if (big_is_negative(x)) {
+    x = make(INT, digit0(x), rest(x));
+    s2 = !s1;
+  }
+
   /* effect: s1 set iff y negative, s2 set iff signs mixed */
-  if (rest(y))
+  if (rest(y)) {
     longdiv(x, y);
-  else
+  } else {
     shortdiv(x, digit(y));
+  }
+
   if (s2) {
-    if (!bigzero(b_rem))
+    if (!bigzero(b_rem)) {
       b_rem = bigsub(y, b_rem);
+    }
   }
   return (s1 ? bignegate(b_rem) : b_rem);
 }